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arXiv · 2302.09013

Uniformity Testing over Hypergrids with Subcube Conditioning

Xi Chen·Cassandra Marcussen
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Abstract

We give an algorithm for testing uniformity of distributions supported on hypergrids $[m_1] \times \cdots \times [m_n]$, which makes $\smash{\widetilde{O}(\text{poly}(m)\sqrt{n}/\epsilon^2)}$ many queries to a subcube conditional sampling oracle with $m=\max_i m_i$. When $m$ is a constant, our algorithm is nearly optimal and strengthens the algorithm of [CCK+21] which has the same query complexity but works for hypercubes $\{\pm 1\}^n$ only. A key technical contribution behind the analysis of our algorithm is a proof of a robust version of Pisier's inequality for functions over hypergrids using Fourier analysis.

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Xi Chen, Cassandra Marcussen. 2023-02-17. Uniformity Testing over Hypergrids with Subcube Conditioning. https://arxiv.org/abs/2302.09013

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